A. Its Field.
Shielding enclosures are utilized for anechoic chambers, communication facilities, mobile communications, computer facilities, test units, securement-of-conference-room communications, clean rooms, and the prevention or regulation of electrical and other signals in the atmosphere or space. An opening or door entryway is needed in or through each enclosure for ingress and egress hereinafter `access`) by personnel to and from the enclosure's compartment or into or from a closed enclave continuously attached to such a compartment. Thus, an efficacious sealing mode between the enclosure's wall panel and the door across its entryway or opening must be achieved in order to prevent leakage of any radio-frequency or electro-magnetic radiation out of or into the enclosure. In constructing and assembling these systems, each is built to a particular specification by the user for a given range or ranges of signals, as in reality heretofore, leakage has occurred. Thus heretofore, the specification was drawn to meet a maximum of leakage allowed in a particular constructed system. The performance of meeting such leakage maximum was measured by the attenuation of a loss of leakage for a given constructed or built enclosure or system.
B. Problems in the Prior Art.
A major problem facing the shielding enclosure industry is the lack of solving a frequency-wave penetration through a door assembly mounted across the opening or entry (exit) way to the enclosure's compartment. Perforations, holes, openings somewhere in or about the door assembly were present as a result of the requirement for operating elements to open and/or close the door whereby personnel could gain access in either direction. Thus, these deficiencies would serve as bases for conduits through which leakage of radio-frequency waves would occur, by their passage or radiation either way. Present state-of-the-art enclosures include construction and/or design which attenuate such leakage of radio frequency (R-F) waves to various degrees, but never eliminating the leakage. This invention substantially eleminates the problem of leakage.
C. Description of the Prior Art.
See my U.S. Pat. No. 4,590,710, granted May 27, 1986, together with identification of prior art teachings set forth in the specification and Abstract of that patent.